So far, DNA-damaging substances (physical and chemical carcinogens) which cause the breakage of DNA strands have been identified by measuring the strand breakage either in cell lysates by alkaline DNA denaturation methods (e.g., "alkaline elution") or in situ by means of individual cells (what is called "comet assay"). However, the lysate tests included the drawback that they were technically relatively complicated and required the experimenter's great manual skill. In "comet assays" the reading is also carried out by means of a microscope, which calls for the employment of a complicated apparatus.
Therefore, the object underlying the present invention is to provide a process for rapidly and reliably identifying chemical carcinogens.